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Located in central Washington State, Banks Lake serves as an irrigation storage reservoir for the Columbia Basin Irrigation Project and is home to a diverse fisheries population. The current hydrologic management strategies used for Banks Lake have been chosen to serve two purposes: to adequately store and provide irrigation water for the Columbia Basin Irrigation Project and to maintain a healthy aquatic environment suitable for the growth and habitation of local flora and fauna. Increased needs for irrigation water within arid central Washington poses additional challenges to reservoir managers so that irrigation needs are met without damaging the present aquatic environment within Banks Lake. Future plans by the Washington Department of Ecology to use Banks Lake storage to replenish ground water reserves of the Odessa Subarea aquifer have required an investigation into how increased seasonal drawdown may affect fish growth, fish habitat and overall limnology of Banks Lake. The goal of this project is to produce a hydrodynamic and water quality model of Banks Lake that can predict the impacts of management strategies on the lake's water quality and the linkage of lake management to fish habitat.

Indiana University-Purdue University Indianapolis (IUPUI) / The transfer of nutrients from US Midwest croplands into surface waters causes eutrophication and a decline in water quality. Temporary retention of nutrient-rich runoff in constructed wetlands can help mitigate these negative impacts through physical entrapment and biological transformation of nitrogen (N) and phosphorus (P). However, with the expectation that wet-dry periods will be more frequent in the region, there is a need to better understand the mechanisms that control nutrient retention and release in US Midwest wetlands constructed on former croplands. In this study, soil cores (30 cm long, 20 cm diam) were collected from two constructed wetlands (4 and 8-yr old), and the surface (0-20 cm) and subsurface (40-60 cm) layers of a cropland where a constructed wetland will be constructed in the future. Soil cores were subjected to either a moist or a dry treatment for 5 weeks, and then flooded with stream water (water depth 6 cm). The flux of nutrients, N2O, cations, and variation in floodwater chemistry (pH and ORP) were monitored for another 5 week period. Porewater was tested during the final 3 weeks of the experiment. Nitrate (0.1-130 mg N m-2 d-1) and inorganic P (Pi) fluxes (0.09-2.9 mg P m-2 d-1) were significantly higher in the dry treatment cores. Regardless of site, the dry treatment also resulted in higher floodwater NO3- concentrations suggesting organic matter mineralization and mineral N build up during the drying phase. However, this initial NO3- release was rapidly denitrified as indicated by the sharp increase in N2O production during that period. In contrast to N, the release of Pi was significantly higher in cores from the cropland. Soil at these sites had higher water extractable Pi and total P. Contrary to the study hypothesis and the results of previous studies, Pi concentration in floodwater and porewater was not correlated with dissolved Fe suggesting that reductive dissolution was not the dominant process controlling P release in US Midwest mineral soils developed from calcareous glacial till. Rather, variation in Ca2+ concentration and its relationship with Pi suggest that dissolution of Ca-containing minerals may be more important and should be the focus of future studies examining the geochemistry of P in these constructed wetlands.

The effect of stormwater runoff on the water quality of Peters Creek was investigated. Creek water was sampled at rural, suburban and urban sites. Background and runoff samples were analyzed for sediment, nutrient and heavy metal concentrations. The area upstream of the suburban site was found to contribute the greatest contamination to the creek but the heavy metal contributions were accumulated throughout the watershed. The creek water contained sufficient nutrients to potentially contribute to the eutrophication of Smith Mountain Lake downstream. As the watershed has been developed, flooding has increased in frequency. The detrimental effects of runoff can be reduced in the watershed by clearing the trash from the creek bed, enforcing construction erosion control and creek bed alteration ordinances and by building a series of detention basins in the creek upstream from common sites of flooding. / Master of Science / incomplete_metadata

Water Quality Management is one of the critical challenges currently facing South Africa. The triad of water resource management, socio- economic development and environmental sustainability are key issues that require balance and compromise. The effects of anthropogenic activities on the Blesbokspruit catchment were examined. Water samples were collected from nine strategically selected sites along the stream for a period of ten months in six weekly intervals and analysed for physio-chemical, selected trace metals and microbial entities. Results revealed that variables of concern were Electrical Conductivity (EC), Total Suspended Solids (TSS), Nitrates, Phosphates, Sulphates and Chemical Oxygen Demand (COD). Mean levels of these parameters in this order ranged from 93.0-146.63mS/m; 11.25-39mg/L; 0.16-2.01mg/L; 0.5-0.96mg/L; 118.63-379.5mg/L and 15.0-34.0mg/L respectively. Levels of E. coli and F. coliforms also ranged from 19.13- 43999.125 cfu/100mL and 20.63-16878.5 cfu/100mL respectively which were of concern. Levels of analysed trace metals were tolerable except for Fe with a range of 0.04- 0.73mg/L. Generally, the results from this study indicate that the river is contaminated and therefore not suitable for direct human consumption as well as for irrigation purposes.

Water Quality Management is one of the critical challenges currently facing South Africa. The triad of water resource management, socio- economic development and environmental sustainability are key issues that require balance and compromise. The effects of anthropogenic activities on the Blesbokspruit catchment were examined. Water samples were collected from nine strategically selected sites along the stream for a period of ten months in six weekly intervals and analysed for physio-chemical, selected trace metals and microbial entities. Results revealed that variables of concern were Electrical Conductivity (EC), Total Suspended Solids (TSS), Nitrates, Phosphates, Sulphates and Chemical Oxygen Demand (COD). Mean levels of these parameters in this order ranged from 93.0-146.63mS/m; 11.25-39mg/L; 0.16-2.01mg/L; 0.5-0.96mg/L; 118.63-379.5mg/L and 15.0-34.0mg/L respectively. Levels of E. coli and F. coliforms also ranged from 19.13- 43999.125 cfu/100mL and 20.63-16878.5 cfu/100mL respectively which were of concern. Levels of analysed trace metals were tolerable except for Fe with a range of 0.04- 0.73mg/L. Generally, the results from this study indicate that the river is contaminated and therefore not suitable for direct human consumption as well as for irrigation purposes.

Thesis (MSc)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: The Saldanha-Langebaan coastal zone is an important natural resource and serves as habitat for several endangered bird and fish species. Development in this coastal zone holds a constant threat for the natural environment and has a negative impact on the water quality of the bay. It is therefore essential to manage the water quality to ensure fitness for use for all the beneficial users in this coastal zone. This study focuses on the utilization and management of the Saldanha-Langebaan coastal zone. The beneficial users have different water quality requirements. It is therefore important to identify all the different water uses and to determine the occurrence of pollution and the dispersion thereof in the bay. The biophysical characteristics of the natural resource are described as part of the objective determining phase of the integrated water quality management process. The thesis also focuses on the inauguration and functioning of an integrated water quality management organization and the development and implementation of a long term monitoring program, with special emphasis on the sediment en health monitoring results. The result of this research study is a functional management instrument for integrated water quality monitoring and management in the Saldanha-Langebaan coastal zone. / AFRIKAANSE OPSOMMING: Die Saldanha-Langebaan kussone is 'n belangrike natuurlike hulpbron en dien as habitat vir verskeie bedreigde voel- en visspesies. Hierdie kussone is egter ook onder konstante ontwikkelingsdruk wat 'n negatiewe impak op die watergehalte van die baai het. Dit is dus noodsaaklik dat die watergehalte so bestuur word dat dit geskik bly vir al die gemeenskaplike watergebruikers in hierdie kussone. In hierdie studie is die benutting en bestuur van die Saldanha-Langebaan kussone ondersoek. Verskillende watergebruikers het uiteenlopende watergehaltebehoeftes en dit is noodsaaklik om die verskillende watergebruikers, sowel as die voorkoms en verspreiding van besoedeling in hierdie gebied te identifiseer. Die biofisiese eienskappe van die natuurlike kusopvanggebied is beskryf as deel van die aanvanklike doelwitbepalingsfase van geïntegreerde watergehaltebestuur. Die tesis fokus ook op die stigting en werkswyse van 'n geïntegreerde watergehaltebestuursliggaam, asook die ontwerp en implementering van 'n langtermyn moniteringsprogram. Daar is veral gelet op die resultate van die . sediment- en bakteriologiese moniteringsprogram. Die resultaat van die navorsingsproses is die totstandkoming van 'n funksionele bestuursliggaam wat as instrument dien vir geïntegreerde monitering en bestuur van die watergehalte in die Saldanha-Langebaan kussone.

Although the use of pesticides is necessary to meet the socio-economic needs of many developing countries, especially in Africa, side effects of these bio-active chemicals have contributed to contaminating aquatic and terrestrial ecosystems. Environmental water quality degradation by pesticides interferes with ecosystem health and poses numerous risks to aquatic life. In South Africa, glyphosate-based herbicides are frequently used to control weeds and invading alien plants, but ultimately end up in freshwater ecosystems. However, there are no South African-based environmental water quality management strategies to regulate these bio-active chemicals. Therefore, this study sought to provide a sound scientific background for the environmental water quality management of glyphosate-based herbicides in South Africa, by conducting both laboratory and field investigations. In the laboratory investigations, aquatic ecotoxicological methods were used to evaluate responses of the freshwater aquatic shrimp Caridina nilotica exposed to Roundup® at different biological system scales, and the responses of multiple South African aquatic species exposed to Roundup® through species sensitivity distribution (SSD). In the field investigations, the effect of Kilo Max WSG on the physicochemical and biological conditions of three selected sites in the Swartkops River before and after a spray episode by Working for Water were evaluated through biomonitoring, using the South African Scoring System version 5 (SASS5) as a sampling protocol. Both Roundup® and Kilo Max WSG are glyphosate-based herbicides. All the data were subjected to relevant statistical analyses. Findings of this study revealed that Roundup® elicited responses at different biological system scales in C. nilotica, while SSD estimates were used to derive proposed water quality guidelines for glyphosate-based herbicides in South Africa. The biomonitoring revealed that using glyphosate-based herbicides to control water hyacinth within the Swartkops River had a negligible impact on the physicochemical and biological conditions. Based on these findings, a conceptual framework that can be used for the integrated environmental water quality management of glyphosate-based herbicides in South Africa was developed as part of integrated water resource management (IWRM). The combined data sets contribute to a sound scientific basis for the environmental water quality management of glyphosate-based herbicides in South Africa.

Water quality deterioration is reaching crisis proportions in South Africa. Many South African catchments are over-allocated, and decreasing volumes of source water mean increasing concentrations of pollutants. The Crocodile River Catchment in the Mpumalanga province in South Africa was identified through previous research, as a catchment faced with deteriorating source water quality for water users in the catchment. Poor source water quality has become a sufficiently acute concern for the stakeholders in this catchment to co-operate in developing a process that assists with compliance control of their water use and waste disposal to reduce costs, decrease industrial risks as water quality compliance increases, and improve source water quality. The sugar industry is downstream within the Crocodile River Catchment, and is affected by the activities of all upstream water users; the industry is thus dependent on the stakeholders upstream participating in the effective management of the resource. However, the sugar industry is also located just before the confluence of the Crocodile River and Komati River upstream of the Mozambique border, and thus the water quality of the sugar industry effluent will affect the quality of the water that flows into Mozambique. The sugar industry is on the opposite river bank to the Kruger National Park, which has high water resource protection goals. Therefore, the sugar industry has a national role to play in the management of water resources in the Crocodile River Catchment. This study provides a focused view of the role of the sugar industry in the development of a co-operative, integrated water quality management process (IWQMP) in the Crocodile River Catchment. In order to address the objectives of this study, this research drew from an understanding of the social processes that influence water management practices within the sugar industry as well as social processes that influence the role of the Inkomati-Usuthu Catchment Management Agency as the main governing institution in water resource management in the Inkomati Water Management Area. The study also drew from an understanding of scientific knowledge in terms of a water chemistry which describes the upstream and downstream water quality impacts related to the sugar industry. The water quality analysis for the Lower Crocodile River Catchment shows a decline in water quality in terms of Total Dissolved Solids (TDS) loads when moving from below Mbombela to the Mozambique border. The major sources of TDS in the Lower Crocodile River are point source dominated, which may be attributed to the extensive mining, industrial and municipal activities that occur across the catchment. When observing Total Alkalinity (TAL) and pH values from below Mbombela to the furthest monitoring point, there is deterioration in the quality of the water in the Lower Crocodile River, with the Kaap River contributing a negative effect that is diluted by the Crocodile main stem. The Hectorspruit Waste Water Treatment Works (WWTWs) (located in the Lower Crocodile River Catchment) contributes high concentrations of TDS and TAL into the Crocodile River. Total Inorganic Nitrogen and Soluble Reactive Phosphorus concentrations decrease in the lower reaches of the Crocodile River compared with the river below Mbombela, which can be attributed to the extensive sugar cane plantations located in the Lower Crocodile River Catchment acting as an “agricultural wetland” that serves a function of bioremediation resulting in large scale absorption of nutrients. This is an interesting result as earlier assumptions were that fertiliser application would result in an overall increase in nutrient loads and concentrations. Biomonitoring data show no substantial change in aquatic health in the LowerCrocodile River Catchment. For a catchment that has an extensive agricultural land use in terms of sugarcane and citrus production, the Crocodile River is unexpectedly not in a toxic state in terms of aquatic health. This is a positive result and it suggests that pesticide use is strictly controlled in the sugar and citrus industry in the Crocodile River Catchment. For long term sustainability, it is essential for the sugar industry to maintain (and possibly improve) this pesticide management. The social component of this study aimed to provide an analysis of the management practices of the sugar mill as well as examining agricultural practices in the sugar cane fields in relation to water quality management through the use of Cultural Historical Activity System Theory (CHAT). This component showed that there are contradictions within the sugar industry activity system that are considered to be areas of “tension” that can be loosened or focused on to improve the contribution the sugar industry can make to the IWQMP. Surfacing contradictions within the sugar industry activity system and the Inkomati-Usuthu Catchment Management Agency activity systems highlighted areas of potential for learning and change. While an understanding of biophysical processes through scientific knowledge is critical in water management decision making, it is evident that an understanding of other actors, institutions and networks that inform water quality management decision-making also plays a significant role. The notion of improving the role of scientific or biophysical knowledge in contributing to socio-ecologically robust knowledge co-creation, decisions and actions towards resolving water quality problems is emphasised. Specifically, moving towards improving interactions between scientists and other actors (water users in the Crocodile Catchment in this case), so that scientific practices become more orientated towards societal platforms where water quality management is tackled to enable improved water quality management practices. Therefore, linking the social and biophysical components in this study provides a holistic understanding of how the sugar industry can contribute to the development of an IWQMP for the Crocodile River catchment.